Make layer comments and labels readable in expressions

[RobBarrett]

Currently, it's not possible to read a layer's comment or label in an expression*. It would be helpful to be able to access these via something like 'layer.comment' or 'layer.label'.

This would allow, for instance, changing a layer's colour based on the comment text or the label.

(*If I've missed something and this is possible, I'll happily be proven wrong!)

[Roland Kahlenberg]

https://ae-expressions.docsforadobe.dev/objects/markerkey/#markerkeycomment

PS - Sorry, I missread it as marker comment.